What Are the Brown Spots on Bananas?

Starch

• The brown-spots on a banana indicate the starch-to-sugar process is nearly 100 percent complete, which is why ripe bananas taste so much sweeter than green bananas.

Chlorophyll

• The chlorophyll in banana peels break down into particles called FCCs (fluorescent chlorophyll catabolites).

UV Light

• A ripe banana, in visible light, is yellow with brown spots; however, when observed under ultraviolet light, the ordinary brown spots glow blue, according to the National Science Foundation.

Research

• A glowing halo occurs close to the dying tissue on the banana peel. Studies of the glowing blue halo, which occur close to dying tissue, provide a promising way to study apoptosis, or "programmed cell death," according to the National Science Foundation.

Fun Fact

• According to the Oxford Dictionary, the banana plant, though called a banana-tree is not a tree but an herbaceous plant, or herb, meaning the plant stem does not contain true woody tissue.